Buggy code:
private boolean latency = SampleSaveConfiguration . _latency ; private boolean timestamp = SampleSaveConfiguration . _timestamp ; private boolean success = SampleSaveConfiguration . _success ; private boolean label = SampleSaveConfiguration . _label ; private boolean code = SampleSaveConfiguration . _code ; private boolean message = SampleSaveConfiguration . _message ; private boolean threadName = SampleSaveConfiguration . _threadName ; private boolean dataType = SampleSaveConfiguration . _dataType ; private boolean encoding = SampleSaveConfiguration . _encoding ; private boolean assertions = SampleSaveConfiguration . _assertions ; private boolean subresults = SampleSaveConfiguration . _subresults ; private boolean responseData = SampleSaveConfiguration . _responseData ; private boolean samplerData = SampleSaveConfiguration . _samplerData ; private boolean xml = SampleSaveConfiguration . _xml ; private boolean fieldNames = SampleSaveConfiguration . _fieldNames ; private boolean responseHeaders = SampleSaveConfiguration . _responseHeaders ; private boolean requestHeaders = SampleSaveConfiguration . _requestHeaders ; private boolean responseDataOnError = SampleSaveConfiguration . _responseDataOnError ; private boolean saveAssertionResultsFailureMessage = SampleSaveConfiguration . _saveAssertionResultsFailureMessage ; private boolean url = SampleSaveConfiguration . _url ; private boolean bytes = SampleSaveConfiguration . _bytes ; private boolean fileName = SampleSaveConfiguration . _fileName ; private boolean threadCounts = SampleSaveConfiguration . _threadCounts ; private boolean sampleCount = SampleSaveConfiguration . _sampleCount ; private int assertionsResultsToSave = SampleSaveConfiguration . _assertionsResultsToSave ; private boolean printMilliseconds = SampleSaveConfiguration . _printMilliseconds ; private transient DateFormat formatter = SampleSaveConfiguration . _formatter ; private static final boolean _time ; private static final boolean _timestamp ; private static final boolean _success ; private static final boolean _label ; private static final boolean _code ; private static final boolean _message ; private static final boolean _threadName ; private static final boolean _xml ; private static final boolean _responseData ; private static final boolean _dataType ; private static final boolean _encoding ; private static final boolean _assertions ; private static final boolean _latency ; private static final boolean _subresults ; private static final boolean _samplerData ; private static final boolean _fieldNames ; private static final boolean _responseHeaders ; private static final boolean _requestHeaders ; private static final boolean _responseDataOnError ; private static final boolean _saveAssertionResultsFailureMessage ; private static final String _timeStampFormat ; private static int _assertionsResultsToSave ; public static final int SAVE_NO_ASSERTIONS = 0 ; public static final int SAVE_FIRST_ASSERTION = ( SampleSaveConfiguration . SAVE_NO_ASSERTIONS ) + 1 ; public static final int SAVE_ALL_ASSERTIONS = ( SampleSaveConfiguration . SAVE_FIRST_ASSERTION ) + 1 ; private static final boolean _printMilliseconds ; private static final boolean _bytes ; private static final boolean _url ; private static final boolean _fileName ; private static final boolean _threadCounts ; private static final boolean _sampleCount ; private static final DateFormat _formatter ; private static final String _delimiter ; private static final String DEFAULT_DELIMITER = "," ; private String delimiter = SampleSaveConfiguration . _delimiter ; private static final SampleSaveConfiguration _static = new SampleSaveConfiguration ( ) ; public static SampleSaveConfiguration staticConfig ( ) { } public SampleSaveConfiguration ( ) { } public SampleSaveConfiguration ( boolean value ) { } private Object readResolve ( ) throws ObjectStreamException { } public Object clone ( ) { } public boolean equals ( Object obj ) { } public int hashCode ( ) { } public boolean saveResponseHeaders ( ) { } public void setResponseHeaders ( boolean r ) { } public boolean saveRequestHeaders ( ) { } public void setRequestHeaders ( boolean r ) { } public boolean saveAssertions ( ) { } public void setAssertions ( boolean assertions ) { } public boolean saveCode ( ) { } public void setCode ( boolean code ) { } public boolean saveDataType ( ) { } public void setDataType ( boolean dataType ) { } public boolean saveEncoding ( ) { } public void setEncoding ( boolean encoding ) { } public boolean saveLabel ( ) { } public void setLabel ( boolean label ) { } public boolean saveLatency ( ) { } public void setLatency ( boolean latency ) { } public boolean saveMessage ( ) { } public void setMessage ( boolean message ) { } public boolean saveResponseData ( SampleResult res ) { } public boolean saveResponseData ( ) { } public void setResponseData ( boolean responseData ) { } public boolean saveSamplerData ( SampleResult res ) { } public boolean saveSamplerData ( ) { } public void setSamplerData ( boolean samplerData ) { } public boolean saveSubresults ( ) { } public void setSubresults ( boolean subresults ) { } public boolean saveSuccess ( ) { } public void setSuccess ( boolean success ) { } public boolean saveThreadName ( ) { } public void setThreadName ( boolean threadName ) { } public boolean saveTime ( ) { } public void setTime ( boolean time ) { } public boolean saveTimestamp ( ) { } public void setTimestamp ( boolean timestamp ) { } public boolean saveAsXml ( ) { } public void setAsXml ( boolean xml ) { } public boolean saveFieldNames ( ) { } public void setFieldNames ( boolean printFieldNames ) { } public boolean saveUrl ( ) { } public void setUrl ( boolean save ) { } public boolean saveBytes ( ) { } public void setBytes ( boolean save ) { } public boolean saveFileName ( ) { } public void setFileName ( boolean save ) { } public boolean saveAssertionResultsFailureMessage ( ) { } public void setAssertionResultsFailureMessage ( boolean b ) { } public boolean saveThreadCounts ( ) { } public void setThreadCounts ( boolean save ) { } public boolean saveSampleCount ( ) { } public void setSampleCount ( boolean save ) { } public void setFormatter ( DateFormat fmt ) { <START_BUG> printMilliseconds = "ms" . equals ( fmt ) ; <END_BUG> formatter = fmt ; } public boolean printMilliseconds ( ) { } public DateFormat formatter ( ) { } public int assertionsResultsToSave ( ) { } public String getDelimiter ( ) { } public String getXmlPi ( ) { } public void setDelimiter ( String delim ) { } public void setDefaultDelimiter ( ) { } public void setDefaultTimeStampFormat ( ) { } }

Fix:
printMilliseconds = fmt == null ;